Indirect visual monitoring system is a type of patient monitoring system widely using till now in the radiotherapy. Time at which the radiation was started as treatment for cancer direct visual communication used widely (Lead window type). Later on the emergent of indirect visual patient monitoring systems slowly removed the usage of direct visual system by its unique advantage.

Indirect visual patient monitoring system has two types,

1. One type of that is Closed Circuit Television (CCTV) system. This was very helpful and most succeeded way of indirect visual patient monitoring system till now.

2. Another type of indirect visual patient monitoring system is using the mirrors inside the treatment room.

Closed Circuit Television (CCTV): CCTV system is the one of the most successful system till now in the field of radiotherapy. The advantage of the CCTV system is we can see the entire treatment room during the treatment including the patient. No additional personnel are required to monitor the patient. Good clarity of the image through the CCTV leads to monitoring the patient clearly and accurately during the treatment; slight movements in the patients can also be detected.

The above diagram shows the CCTV based monitoring system in Dr. B.Borooah Cancer Institute, India.Mirror based patient monitoring system.

Mirror based patient monitoring system has been used as an alternate method in telecobalt machines. If, there is any failure in CCTV system, mirror based system was used. In some hospitals would have only the mirror based monitoring system to monitor the patient during the treatment. In this system two mirrors will be used and each fixed at angle of 45◦ angle so that clearly seen through the glass window doors from the console control. With the help of this mirror system the source on and off position of the telecobalt machine also can be found.In linear Accelerators only CCTV based patient monitoring system is in practice.

Questions:1. What is the advantage the indirect visual patient monitoring system?a) We can see the patient lucidly through CCTVb) Reducing the personnel required for monitoringc) Reduces the cost of lead window type monitoring.d) All